Key slot plug



DCC- 15, 1953 D. N. MICHNOFF ET AL 2,662,390

' KEY SLOT PLUG Filed April 25, 1949 2 Sheets-Sheet l 5 ff Ulf/ 014. A.

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KEY SLOT PLUG Filed April 25. 1949 2 Sheets-$heet 2 "Ava" atented Dec.15, 1953 UNITED E T F F l C I.

KEY SLOT PLUG David N. lifiichnofi, Brooklyn, N. Y., and Charles lvl.Falmer, Washington, D. C.

The subject matter of this invention is a serviceable and compositesplit key having vas one object to utilize one component thereof as aper sonal key plug for a key slot of a conventional cylinder lockalthough in its broadest application the invention is not limited inthis respect. An other object resides in the provision of a novel keyblank havinQV separable upper and lower cornu plementary componentsdefining split shank means adapted to be held together by connector orkeeper means unlocked from the upper `component in the fully closedposition of an appropriate retaining clasp which houses the split shankin its assembled relation. Another object is realized in actuating thekeeper by the retaining clasp on the opening throw of the latter forlocking the upper and lower components or complements in their assembledrelation. Another object resides in the provision of means for quicl lypermitting the lower complement to be removed irom the upper complementand keeper upon partial opening of the retaining clasp. Other importantobjects are specifically concerned with a U shaped retaining clasp forhousing and straddling the split shank and having suitable locking meansto preclude the assembled shank from accidental falling out of theclasp; the provision oi cam shaped means on the clasp for actuatingr thekeeper or connector means on the closing stroke oi the clasp and theprovision oi finger means for operating the keeper means to its lockingrelation on the opening stroke oi the clasp. Gther objects, advantages,and functional and structural features of the invention will appear fromthe following detailed specification taken with the accompanyingdrawings wherein:

Fig. 1 is a iront elevational view of the device according to ourinvention illustrating the keeper unlocked from the lower and separablecomplement of the composite key blank and retaining clasp closelystraddling and covering the composite blank but maintaining theswingable keeper released.

Fig. 2 is a rear view of Fig. l.

Fig. 3 is a view similar to Fig. 1 however showing in full lines theclasp or casing partly raised to permit convenient removal of the lowercornplement of the composite blank from the keeper as illustrated bydash lines.

Fig. 4 is a vertical sectional view of a conventional cylinder lock withthe lower complement of the composite key blank locked againstwithdrawal in the key receiving slot thereof.

Fig. 5 is a view similar to Fig. 3 however depicting the uppercomplement of the key blank in place over the lower complement and theretaining clasp or handle rotating in a clockwise direction toultimately actuate the U shaped keeper now unlocked from the lowercomplement.

Fig. 6 is a View similar to Fig. 5 but with the retaining clasp nowabutting the keeper to aotu `ate and throw the latter to removablyinterlock with the upper complement of the split and comn posits keyblank.

Fig. 7 illustrates the retaining clasp in its fully opened positionafter having thrown the keeper to lock the upper and lower complementsof the key blank.

Fig. 8 illustrates the composite key blank in a locked relation andinserted into the key receiving slot oi the cylinder lock.

Fig. 9 is a plan view of Fig. il.

Fig. 1G is an enlarged transverse sectional viev.7 on the line lillll ofFig. 1.

Fig. l1 is a perspective view of the swingable retaining clasp.

Fig. 12 is a perspective view of the hinged keeper.

Fig. 13 is a front elevational view of a conventional cylinder lock.

Fig. 14 is a side elevational View according to another embodiment ofthe invention illustrating the complements of the split shank heldtogether by a slidable keeper.

Fig. 15 is a perspective view of Fig. 14 however with the lowercomplement detached.

Fig. 16 is a sectional View on the line Iii-I@ oi. Fig. 14.

Iig. 17 is a view on the line lll-ll of Fig. 14 an Fig. 18 is atransverse sectional view on the line it--IS of Fig. 14.

Illustrative of the embodiments disclosed the composite and split keyblank broadly denoted l. has its shank S appropriately split by thelongitudinal rectilinear cut l il, the meeting biased but straight kerfH and the vertical out i2 to denne two separable parts or components,namely, a lower complement LC and an upper complement UC. As is wellunderstood shank S is provided with a conventional rib it and slots i5and le? (Figs. 8 and l0) for convenient reception in the mating keywayor slot il of the cylinder plug ill (Fig. 13) oi' the cylinder lock CL,however it should be observed that cut l@ in part divides rib l llongitudinally thereof.

According to the invention, the lower cornplement LC is interrupted bythe reentrant slot 2t for reception and interlocking with web il bridging sides 22 of the U shaped keeper 23 swingably or hingedly mounted onfulcrum pin 24 fastened to the bow B of the key blank K. If the keeperbe unlocked or released from the upper complement UP of course sides 22pivotally straddle bow B and lugs or lips 32 thereof although new freeof the upper complement now removably and closely straddle the sides ofthe lower complement LC but if the keeper be locked to the lowercomplement these lips or shoulders 32 closely straddle the sides of theupper complement UC and thus interlock with the latter. This lockingaction is accomplished when the finger or cam F of the swingable Ushaped retaining clasp has shifted from its unlocking position shown inFigs. 1 and 3 to the locking position shown in Fig. 8.

The keeper operating finger F (Fig. 11) constitutes an extension of oneof the spaced arms 24' of spaced sides 25 of the hollow retaining claspor cover RC which embodies brace 2G merged with sides 25 and one of thelatter is provided with an inwardly turned flange 2 serving to properlymaintain and space sides 25 apart.

As shown, arms 24 are provided with the spaced areas 28 closelystraddling bow B. These ears are rotatably retained on the fulcrum pin29 which is xed to the bow B of the key blank. Thus the clasp or hollowcasing RC may be swung or pivoted relative to the bow B.

With the spit key blank K assembled as shown in Figs. 1 and 2, sides 25of the clasp or casing RC slightly frictionally straddle and embrace thesides of the superimposed complements or components LC and UC to preventthe blank from accidentally pivoting out of the clasp. To supplementsuch action one of the sides 25 includes the struck in dimple or dentent30 to permit shank S to snap by detent 30 to disengageably lock thelower complement within the clasp RC which in its fully closed relation(Figs. 1 and 2.) houses the upper and lower complements of the shank atwhich time as heretofore alluded to the pivoted keeper 23 is free andclear of the sides of the upper complement UC, that is, unlockedtherefrom. This unlocking action or release of the keeper was caused bythe spaced cam shaped faces 3I of the spaced arms 24 of the claspabutting the spaced lips as shoulders 32 when the U shaped clasp RC wasrotated to its full closed position (Figs. 1 and 2). It follows thatalthough shank S is now prevented from accidentally shifting from theclasp, the keeper is biased but unlocked from the upper separablecomplement UC, however at such time bridge or web 2I of the U shapedkeeper or hasp 23 just clears, that is, out of the relief slot of thelower complement LC but the tooth I3 of the latter is still within thekeeper and behind web 2l.

If the clasp RC be now opened to be free of the split shank S (Fig. 3)the lower complement LC may be quickly separated from the uppercornplement and also easily detached from the keeper 23. For example, asshown in full lines in Fig. 3, the split shank is unlocked fromthe-clasp RC and the lower complement may be removed free of the keeperand even from the upper complement and consequently tooth I3 of thelower complement may be quickly removed from behind web 2I of the keeper23, hence completely detaching the lower complement from its uppercompanion complement UC. It follows that the lower complement may now beconveniently inserted in the keyway I1 of the cylinder lock CL (Fig. 4)wherein several of the. spring controlledl tumblers as T are inadvanceof lip or extension 34 of the lower complement to precludewithdrawal of the latter from the cylinder lock. Consequently the lowercomplement LC is now held locked in key slot I'I, acting as a plugtherefor to resist unauthorized tampering with several of the tumblers,thus serving as a measure of safety. Of course lip 34 is adapted toactuate the several tumblers in the key slot or keyway Il' uponinsertion of the lower complement therein and in its fully insertedposition tooth I3 may project slightly beyond the front face of thecylinder lock.

To remove the locked plug or lower complement LC from the key slot orkeyway Il, the upper complement UC is inserted in the keyway above thelower complement. Before such action the keeper 23 is manually tiltedfully downwardly for example, to the position shown in Figs. 2 and 3 topermit at the completion of insertion of the upper complement, andreception of tooth I3 in clearing gap 34 (Fig. 12) defined by spacedshoulders 32 of the swingable keeper 23. Thereafter, handle or clasp RCis rotated in a clockwise direction permitting finger F to throw andactuate the tilted keeper or connector 23 upwardly, causing web 2I ofthe latter to be positioned in relief slot 28 and shoulders 32 tostraddle and interlock with the sides of the upper complement (Fig. 8)and at this time web 2l acts as a seat holding the lower complement LCto the upper complement UC. It follows therefore that the upper andlower complements are now adequately connected by 1Lhe keeper to permittheir removal in unison out of the keyslot Il. This is accomplished bymerely applying an outward thrust cn the clasp RC which in this caseserves as a handle.

During bodily withdrawal of the connected upper and lower complements,web 2l constitutes driving means against tooth I3 to shift the latteroutwardly and of course on the insertion of the upper complement in thekey slot Il while the lower complement is locked therein, the uppercomplement releases or lifts the tumblers T resting on the lowercomplement so that in the assembled relation of both of thesecomplements all of the tumblers of the cylinder lock are at the sameelevation to allow for withdrawal of the split shank S from the cylinderlock and following withdrawal, handle or clasp RC is swungIccunterclockwise relative to the keyblank K, causing sides 2E to receiveand straddle this, blank after which cams SI act on shoulders 32 to tiltthe keeper or connector downwardly to unlock the upper complement andfor clearing of the lower complement and thereafter the detent 30 snapsby the lower complement to lock the shank from tilting out of the claspor casing RC.

In the form according to Figs. 14 to 17, the locking keeper K isslidably guided on the keyblank B and is provided with forwardlyextending wings or lugs 4I) normally straddling the upper and lowercomponents UC and LC in the assembled relation of the keyblank B (Fig.14) at which time web 2 I holds the lower component against the uppercomponent. In such relation, the key blank may be considered asinterlocked with the keeper K which is normally held raised by theaction of the normally expandible spring SP conned within thecylindrical housing H from which spaced wings 40 integrally depend.These wings may be considered a part of the spaced sides 22' of thekeeper K. Spring SP encircles a projection P (Fig. 18) extending from'thel upper complement` UC andabuts the lower end of the housing H andits fixed cap 4|. Housing I-I is interrupted by the relief gap 42 havingwalls straddling the upper and lower complements or components to permitadequate linear displacement of the housing when depressed to shiftwings it downwardly to be free of the upper complement at which time web2l' also clears 'the lower complement, thereby unlocking the latter fordetachment from the upper complement. To assemble the key blank, lug i3'is hooked over web 2l and positioned within the keeper K when thehousing is depressed after which finger pressure on the housing isremoved, and the latter is automatically raised due to the action of thespring. In other aspects, the embodiment according to Figs. 14 to 17 isalong the lines of the form illustrated in Figs. 1-12 although in Figs.lli-17 corresponding parts have been primed.

Various changes may be made in details or" construction and arrangementof parts without departing from the spirit of the invention orsacrificing any of the advantages thereof inherent therein.

We claim:

1. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler' means and comprising comple mentary upper and lowerseparable components, hollow keeper means for straddling said shank fordetachably holding said lower component against said upper component,and actuating means movably mounted on said key blank for displacingsaid keeper means relative to said shank.

2. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components, said lower component having at its rear end a slotand a lug, and a keeper having sides for straddling said components andincluding a web receivable in said slot and an opening for receivingsaid lug.

3. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components, said lower component having at its rear end a slotand a lug, a keeper mounted on said key blank and having sidesstraddling said lower component and including a web removably receivablein said slot for holding said lower component against said uppercomponent and including an opening between said sides for removablyreceiving said lug, and means for displacing said keeper for shiftingsaid sides to removably straddle said upper component.

4. In a device for insertion in a key slot in which tumbler' means aremovably arranged; a key blank having a split shank adapted to actu atesaid tumbler means and comprising comple mentary upper and lowerseparable components, said lower component having at its rear end a slotand a lug, a keeper having sides straddling said lower component andincluding a web removably receivable in said slot for holding said lowercomponent against said upper component and including an opening betweensaid sides for removably receiving said lug, means pivotally holdingsaid keeper on said blank, and means d for displacing said keeper forremovably shifting said sides to straddle said upper component.

5. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components, Said lower component having at its rear end a slotand a lug, a keeper movably mounted on said key blank and having sidesstraddling said lower component and including a web receivable in saidslot for holding said lower component against said upper component andincluding an opening between said sides for receiving said lug, andmeans movably mounted on said key blank for displacing said keeper forshifting said side to straddle said upper component. v

6. In a device for insertion in a key slot i which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components, said lower component having at its rear end a slotand a lug. a keeper movably mounted on said key blank and having sidespivotally straddling said lower component an-d including a web removablyreceivable in said slot for holding said lower component against saidupper component and including an opening between said sides forreceiving said lug, and means pivoted to said key blank for displacingsaid keeper for shifting said sides to straddle said upper component.

7. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components, said lower component having at its rear end a slotand a lug, a keeper having sides straddling said lower component andincluding a web removably receivable in said slot for holding said lowercomponent against said upper components and including an opening betweensaid sides for removably receiving said lug, means pivotally sustainingsaid sides to said key blank, a casing having means for displacing saidkeeper for shifting said sides to straddle said upper component, andmeans pivotally holding said casing to said key blank.

8. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components, said lower component having at its rear end a slotand a lug, a keeper having sides straddling said lower component andincluding a web removably receivable in said slot for holding said lowercomponent against said upper components and including an opening betweensaid sides for removably receiving said lug, means pivotally sustainingsaid sides to said key blank, a displaceable casing for removablyhousing said com ponents and having an extension for displacing saidkeeper on movement of said casing away from said upper component forshifting said sides to removably straddle and interlock with said uppercomponent, and means pivotally holding said casing to said key blank.

9. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components, said lower component having at its rear end a slotand a lug, a keeper having sides straddling said lower component andincluding a web removably receivable in said slot for holding said.lower component against said upper components and including an openingbetween said sides for removably receiving said lug, means pivotallysustaining said sides to said key blank, a casing for housing saidcomponents, means pivotally holding said casing to sai-d key blank,means on shifting of said casing away from said components for actuatingsaid keeper to interlock with said components, and means on said casingon shifting of the latter to close said casing and for unlocking saidkeeper from said components.

10. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components,- said lower component having at its rear end aslot and a lug, a keeper having sides straddling said lower componentand including a web removably receivable in said slot for holding saidlower component against said upper components and including an openingbetween said sides for removably receiving said lug, means pivotallysustaining said sides to said key blank, a casing for removably housingsaid components, means' pivotally holding said casing to said key blank,a

nger exten-ding from said casing for actuating said keeper on shiftingof said casing away from said components to interlock `with saidcomponents, and cam means on shifting of said casing towards saidcomponents and towards the completion of covering of the latter by saidcasing for shifting said keeper to unlock! from said components.

1l. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components, said lower component having at its end a slot anda lug, a keeper having sides including spaced shoulders straddling saidlower component and including' a web removably receivable in said slotfor holding said lower component againstv said upper component andincluding an opening b'etween said sides for removably receiving saidlug, means pivotally sustaining said sides to said keyblank, a casingfor removably housing said components, means pivotally holding saidcasing to said keyblank, and an extension onsaid casing for shifting ofsaid keeper means to actua'te said keeper means for detachably holdingsaid lower component to said upper component, and means mounted on saidkeyblank for removably covering said shank and for actuating said keepermeans.

13. In a device for insertion of a keyslot in which tumbler means aremovably arranged; a keyblank having a split shank adapted to actuatesaid tumbler means and comprising complementary upper and lowerseparable components, keeper means for detachably holding said lowercomponent to said upper component, and means slidably guiding saidkeeper means relative to said key blank.

14. In a device for insertion of a keyslot in which tumbler means aremovably arranged; a keyblank having a split shank adapted to actuatosaid tumbler means and comprising compleinentary upper and lowerseparable components, keeper means for detachably holding said lowercomponent to said upper component and having means for interlocking withsaid components, a housing secured to said keeper and linearlyshifta-ble to move said keeper away from and clear of said uppercomponent, and spring mea-ns normally hol-:ling said housing elevated.

l5. In a device for insertion in a key slot in which tumbler means aremovably arranged; a key blank having a split shank adapted to actuatcsaid tumbler means and comprising complerr `ntary lower separablecomponents, lower component having at its rear end a slot and a lug,keeper having sides straddling said lower component and including a webreceivable in said slot for holding said lower component against saidupper components and including opening between said sides for receivingsaid lug, a housing rnovably straddling said components and secured tosaid sides, and spring means within said housing for normally holdingthe latter elevated.

16. As a new article of manufacture, a key comprising upper and lowercomplements constitilting a shank split in part longitudinally andwidthwise to define complementary and separable upper and lower shankcomponents each including a projection', the projections of said shankcomponents being in alignment and disposed laterally and at the rearends of said components, and said lower projection having a reentrantrecess.

DAVID N. MICHNOFF. CHARLES M. PALMER.

References Cited in the le 0f this patent UNITED STATES PATENTS NumberName Date 1,696,326 Roethlisberger 1 Dec. 25, 1928 1,807,540 MakranczyMay 26, 1931

